Many drugs such as doxorubicin, a potent cancer therapeutic agent, and Amphotericin B, the most effective drug presently known for a broad range of fungal infections, are highly toxic.
Liposome systems have been proposed as bloodstream delivery systems to provide controlled release and to minimize toxic side effects of a variety of encapsulated drugs, such as doxorubicin and Amphotericin B.
Various limitations on intravenous liposome drug delivery have been recognized. Importantly included among these limitations are unduly rapid release or leakage of the encapsulated drug from the liposome and insipid uptake of blood circulatory liposomes by the reticuloendothelial system (RES) which comprises circulating and fixed macrophages.